The health benefits of a well-rounded exercise program have become increasingly well known in recent years. Current medical thinking suggests such a program should include both aerobic and anaerobic exercise. Aerobic exercise is any exercise which conditions the cardiovascular system by increasing the heart rate of the person undergoing the exercise and maintaining that heart rate in an elevated range for at least 10-15 minutes. On the other hand, anaerobic exercise seeks to increase muscle size and the capacity of the muscle for performing work, i.e. the so-called "body building" exercises. Anaerobic exercise does not generally provide any aerobic benefit.
Aerobic exercise can be accomplished by walking, running, swimming or undertaking any physical activity which causes the elevated heart rate. Moreover, various machines have been developed for use as aerobic exercisers. Such machines include stationary bicycles, treadmills, rowing machines, cross country skiing machines and the like. Such machines can also be used indoors and are often desirable when weather conditions would otherwise make it difficult to perform outside forms of aerobic exercise.
Similarly, many devices have been developed to exercise muscle groups anaerobically. The most traditional of these is the freestanding barbell or weight set. In addition, however, various machines have been developed for use in gyms, such as the Universal weight machines or the machines embodied in the Nautilus system. For example, a typical Universal weight machine comprises a rectangular frame having a plurality of stations located along the sides of the frame. A plurality of weight stacks are carried by the frame and are connected to various implements or attachments. The weight stacks can have the weight varied by means of a releasable lock pin. Basically, the operator goes from one station to another performing different exercises at each, for example, the chest press, the leg press and the like.
The Nautilus system is also notable. This system includes many specialized exercise machines which are devoted generally to performing just one, or at most a few, of the many exercises required for exercising all the muscle groups of the body. In fact, there are at least 17 individual machines in the complete Nautilus system for performing in excess of 25 exercises. Each of the machines generally includes a support bench on which the operator sits or lies and a weight stack. The weight stack is connected through a rotatable cam to an implement which the operator rotates or pushes against as the case may be. The purpose of the cam is to cause a relatively constant exercising force against the muscle throughout the entire range of motion of the exercise. Some of the principles behind the Nautilus system, and particularly the use of the cam, are explained in more detail in U.S. Pat. No. 3,858,873 to Jones.
While the Universal and Nautilus systems are effective, they have numerous disadvantages. For example, the basic rectangular Universal exercise machine is relatively heavy, bulky and is limited in the number of exercises it can perform. For example, a second separate machine is required, even in the Universal system, to perform leg curl and leg extension exercises. However, this machine cannot perform leg abduction or adduction exercises. Moreover, the Nautilus system best typifies the practice of having separate machines for performing separate exercises, thereby requiring a vast array of machines to exercise the body in a reasonably complete fashion. Obviously, the expense required in purchasing such machines, and the relatively large area in which such machines need to be installed, render them unfit or unsuitable for use by the consumer in his home. They generally appear only in gymnasiums, health clubs or other organized sports facilities.
In fact, when one considers the equipment available to be purchased by the consumer for home use at the current time, it is relatively limited. Most of this equipment usually involves some type of exercise bench having pivotal rollers at one end which can be used to perform leg extension and leg curl exercises. The other end of the bench often has a crosspiece member for holding barbells or the like. In addition, spring tension exercisers are often included on such benches.
Various recent patents suggest that it would be desirable for a consumer to have in his home an exercise machine for exercising many different muscle groups. U.S. Pat. Nos. 4,429,871 to Flechner and 4,465,274 to Davenport are two recent examples showing how those skilled in the art have approached this problem. The basic thrust behind the devices shown in these patents is to have a support member on which the user sits which allows rotary motion of the arms and legs about the horizontal pivot axes through the knees, elbows and shoulders. However, these machines also allow further pivoting motions about the vertical axes through the hips and the shoulders. The Flechner device accomplishes this by having separate stations at which the user is positioned depending on which type of pivoting motion is required. Davenport accomplishes this by having a separable attachment which connects to the machine when differently oriented pivot axes are required.
While these two patents have recognized the need for a more versatile machine, they again have numerous disadvantages. For example, most of the exercise attachments against which the user pushes to exercise require their own separate hydraulic cylinders as the force resisting elements. The use of so many separate hydraulic cylinders increases the complexity and expense of the machine. Moreover, hydraulic cylinders are not ideally suited for use in the home since they can leak hydraulic fluid. In addition, the approach to solving the problem of exercises requiring movement about the vertical axes through the hips or the shoulders is somewhat clumsily achieved. Basically, it requires totally separate force resisting elements, in one case arranged at a separate station, for accomplishing this. In addition, it also requires the user to be positioned on the support bench in less than the ideal exercise position because of the geometric limitations of the machine.
It has been suggested that electromagnetic brakes have some utility in aerobic exercise machines. For example, U.S. Pat. No. 4,084,810 to Forsman discloses an electromagnetic brake used as the force resister in a stationary bicycle. However, the Applicant is not aware of any electromagnetic brakes used in an exercise machine capable of exercising both sides of the body in an anaerobic fashion. U.S. Pat. No. 4,337,050 to Engalitcheff shows an electromagnetic brake that is mounted to the top of a table. The brake can be pivoted so that its armature shaft is either vertically pointing toward the ceiling or horizontally pointing toward the wall. Various attachments simulating everyday implements, such as screwdrivers or the like, can be attached to the armature. These attachments are then gripped by a person having damaged muscles who attempts to turn the implement in an ordinary fashion to rehabilitate his muscles. While this is a use of an electromagnetic brake in other than a stationary bicycle, it does not teach the use of such a brake in a fashion which is effective as an anaerobic exercise machine.
Finally, Applicant is aware of an International Application, Publication Number WO80/00308, which was published Mar. 6, 1980. This application discloses a device used for measuring muscular strength having a support bench which can be raised up and down on a scissors framework and which can be slid longitudinally front to back on the framework as well. A carriage is arranged to carry a force resistor from one side of the bench to the other for measuring the muscular strength of the muscles on each side of the body. The force resistor is also pivotally arranged so that its working axis can be shifted from a horizontal to a vertical orientation. It is also recognized that some exercise benefit could be obtained from this arrangement.
While the International Application referenced above discloses a movable and pivotable force resistor, it does not disclose an effective exercise machine. For one thing, it appears to disclose testing or exercising only one-half of the body at a time since the brake has to be moved from one side to the other. In addition, it does not disclose use of an electromagnetic brake, but a different type of force resistance means which is relatively complex. In addition, many of the exercises could be accomplished on this mechanism only in less than ideal positions. Accordingly, this publication does not disclose an effective versatile exercise machine.